Internal-combustion engine



Nav. 5, 19 1-6. O FUSCALDQ 2,41%,728

INTERNAL-COMBUSTION ENGINE Filed Jan, 30, 1941 2 Sheets-Sheet 1 v 6977:4100 Fuse/4100 m a- A. '1 1 Nov. 5, 1946,

I o. FUSCALDQ INTERNAL COMBUSTION ENGINE Filed Jan. 30, 1941 2 Sheets-Sheet 2 0mm mmzd Fatented Nov. 5, 1946 INTERNAL-COMBUSTION ENGINE Ottavio Fuscaldo, Milan, Italy; vested in the Alien Property Custodian Application'lanuary 30, 1941, Serial No. 376,679

r In Italy February 28, 1940 For securing said object and other objects and advantages, the invention consists of the improvement disclosedby the following specification, with reference to the attached drawings, given as an example and embodiment, but intended in no way to restrict the novel principles or range of the invention.

In the drawings:

Fig. 1 shows diagrammatically the proportion-. ing device.

Fig. 2 is a side elevation of a four cylinder internal combustion engine to which the device is applied.

Inthe drawings the supercharger draws in air from supply conduit 3| and delivers it through conduit 33 feeding air by manifold A to the various cylinders of the engine M, which may be such as used for propelling aircraft.

In the suction conduit 3| is a. main throttle or air valve 34 controlling the air admissiomwhich throttle, by means of its lever arm 35 and the yieldable link or rod 363| is hand-controllable by throttle lever 38 fulcrumed at 39.

In the same conduit 3| there is provided a second or auxiliary throttle M for additionally restricting the air feed when flying below a certain' altitude, above which the'full air feed and power of the engine is desirable. The throttle to is controlled through its lever arm BI and the rod or link (32 actuated by a control device t3, later described.

The actuating rod 36-37 for the main throttle is yieldable in length, being adapted to be short ened by compression of its spring 44, when the contact finger 15 on rod end 36 meets an adjustable stop 46, set to correspond to full-open position of throttle 36. But the rod can not lengthen more than is allowed by the end 41 of the barrel portion Q8 of the rod end 31 which encloses the spring at.

The control means 43 is of any known pressure-responsive type being shown with manometric or vacuum bellows l9 enclosed in an air-tight chamber 50, wherein operates the prevailing absolute air feeding pressure as produced by the supercharger, with which the chamber is connected by means of a small air pipe 5|. Thus the supercharged pressure determines thev chamber pressure and causes response of the bellows,

.which may actuate directly the air valve 40,.but

is shown as acting through a hydraulic servomotor 52, the known character of which needs no disclosure.

The bellows $9 is not fixed, but is movable longitudinally in the chamber 50, for adjustment purposes and cooperative control of the airvalve It is held retracted rightward by spring 53 all. against the inner end of bearing guide 5% in which slides the stem 55 of the bellows. The position of the stem 55 is set so that when the hand lever St has completely opened the main throttle 3t, and the telescoping link 36-37 beins to shorten, due to the stop it, a contact screw 56 carried by the hand lever 38 contacts and moves the bellows stem 55, compressing spring 53 and opening the auxiliary throttle to further, thus allowing a certain partial supercharging of air, for instance at the take-oil.

The electric current distributor It is shown with circuits for the various injectors I of the engine, e. g. four; and may be energized by a battery i5 when the switch it "is closed. The distributor M is of the type with variable duration of contact and injection, and the variation is preferably controlled by a centrifugal regulator or governor l'l through lever 'l9and link l8.

Details of a suitable distributor are disclosed in said copending application, which also discloses an appropriate electromagnetic'ally controlled injector.

The centrifugal regulator H, or other speed responsive device, whether mechanical, hydraulic or air-driven, cooperates in making it possible to keep within convenient limits the fuel injection pressure in relation to the changes in the speed of the engine, namely making it unnecessary to increase the pressure too much at high eeds. This resultfollows by reason of the regulator controlling the distributor to adjust the angular The fuel supply system comprises a volumetric pump 5 which draws the fuel from tank 'I by means of pipe 8 and feeds it under pressure through pipe 9 to the fuel manifold F whence it is supplied to the injectors I in the intake pipes M of the engine M; sometimes with bypass operable between injections.

An automatic correcting means is disclosed to maintain the proper fuel-air ratio. in relation to the air feed pressure, operating independently of the characteristics and speed of the fuel pump.

It comprises, as disclosed, a vacuum bellows 60, enclosed in a chamber 5! wherein, by means -of air pipe 62, 62' connecting it with the delivery conduit 33 of the supercharger (or with the air intake conduit, when the engine has no supercharger) so that there always prevails in chamber 6| the absolute air feed pressure. The bellows 60 by its variation in length, acts as follows. On expanding, the bellows shifts downwardly the tapering part 63 of a piston or plunger 64 constituting a fuel bypass valve. The bypass route is from fuel pressure pipe 9 through bypass passage 13, 15, 65 to the fuel supply pipe 8. The valve 63, 64 is between pipes I5 and 65, and with lower air pressure more fuel is bypassed, reducing the injection pressure and volume.

Another or auxiliary system or correcting means comprises a bellows 68 within a chamber 69, with a valve or piston on its stem, and a conical end ll. This device is placed-in series with the first corrector, by means of the bypass pipes 13 and 15,, while their discharges are in parallel, valve 10 releasing fuel through pipe M to pipe In the auxiliary correction system, the chamber 69 communicates not with the high pressure air but with the surrounding atmosphere, through hole or vent 75. The operation is that of supplementally adjusting the air-fuel ratio of an engine providedlwith a supercharger, with atmospheric pressure changes as the craft ascends from the ground up to the prescribed altitude at which the full power of the engine is to be established; this being the case with engines intended to operate at preferred altitudes.

The described set of two correction means for adjusting by fuel bypass the fuel-air ratio of the feeding mixture, consists substantially in two pressure responsive devices, such as manometric bellows, both evacuated, these being-inserted for parallel discharge in the fuel bypass; and with their responsive variation in length, said bellows act, each one for itself, so that the bypassage of the fuel is controlled and varied, by the motion of the piston and plunger with its tapering valve end moving along the fixed or seat portion of the valve.

Of these two correction devices, the first or main one 60 operates under influence of the air feed pressure of the engine, limiting or enlarging the section of the passage of the fuel bypass, according to the increase or decrease of supercharged air pressure; while the second or auxiliary device 68 operates under atmospheric pressure so as to reduce or increase the section of,the bypass passage according to the decrease or increase of outer atmopsheric pressure.

This cooperative combination of the two manometric bellows 60 and 58, acting through their associated bypass valves, allows the air-fuel ratio to be kept practically constant, whatever be the operating conditions of the engines, or the altitude of the craft.

' supercharger, the combination of a main throttle in said air duct; an auxiliary throttle in said air duct; 9. stop limiting the opening movement of the main throttle; a manual lever with a yielding connection with the main throttle for opening the main throttle to the limit of its stop; a pressure-responsive capsule with an air-pipe connection with the supercharger to operate said capsule by variation of supercha'rge air pressure; connections from the capsule to the auxiliary throttle to move the auxiliary throttle toward open position with decrease of supercharge air pressure, and vice-versa; a shiftable stem connected with said auxiliary throttle, to open and close said auxiliary throttle, said stem being positioned in the path of movement of said lever; and means on said lever, co-acting with said stem, to shift said stem to open fully the auxiliary throttle after the lever has been moved to fully open the main throttle.

2. The combination as in claim 1 wherein the capsule has a bellows which is spring positioned but bodily shiftable from normal position to open further the auxiliary throttle; and the manual lever has a contact means operable after the main throttle is opened fully to shift the capsule bellows and so open fully the auxiliary throttle.

3. The combination as in claim 1 and wherein the pressure-responsive capsule comprises a bellows enclosed within a chamber connected to receive the supercharge air pressure, whereby the bellows, with lowered surrounding chamber pressu e, lengthens and thus furnishes the actuation for opening further the auxiliary throttle to admit increased air supply.

4. In an internal combustion engine of the type having a supercharger and means for varying the fuel supply, control means for automatically controlling the supply of liquid fuel and the charging of air into the respective cylinders of the engine to proportion automatically the fuelair mixture comprising, a volumetric pump for forcing liquid fuel toward the engine and having an inlet and an outlet, means constituting two independent bypasses between said outlet and said inlet with a bypass valve in each of said bypasses, pressure responsiv means connected to control one of said bypass valves and responsive to the pressure produced by the supercharger, and pressure responsive means connected to control the other of said bypass. valves and responsive to atmospheric pressure, the first pressure responsive means comprising an evacuated bellows within a chamber communicating with the supercharger delivery, and operating to increase bypass of fuel with lower air intake pressure, and the second pressure responsive means comprising an evacuated bellows exteriorly responsive to atmospheric pressure with change of altitude, and operating to decrease bypass of fuel with lowering of atmospheric pressure.

O'ITAVIO FUSCALDO. 

